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Point sources of emerging contaminants along the Colorado River Basin: Source water for the arid Southwestern United States

June 14, 2012

Emerging contaminants (ECs) (e.g., pharmaceuticals, illicit drugs, personal care products) have been detected in waters across the United States. The objective of this study was to evaluate point sources of ECs along the Colorado River, from the headwaters in Colorado to the Gulf of California. At selected locations in the Colorado River Basin (sites in Colorado, Utah, Nevada, Arizona, and California), waste stream tributaries and receiving surface waters were sampled using either grab sampling or polar organic chemical integrative samplers (POCIS). The grab samples were extracted using solid-phase cartridge extraction (SPE), and the POCIS sorbents were transferred into empty SPEs and eluted with methanol. All extracts were prepared for, and analyzed by, liquid chromatography–electrospray-ion trap mass spectrometry (LC–ESI-ITMS). Log DOW values were calculated for all ECs in the study and compared to the empirical data collected. POCIS extracts were screened for the presence of estrogenic chemicals using the yeast estrogen screen (YES) assay. Extracts from the 2008 POCIS deployment in the Las Vegas Wash showed the second highest estrogenicity response. In the grab samples, azithromycin (an antibiotic) was detected in all but one urban waste stream, with concentrations ranging from 30 ng/L to 2800 ng/L. Concentration levels of azithromycin, methamphetamine and pseudoephedrine showed temporal variation from the Tucson WWTP. Those ECs that were detected in the main surface water channels (those that are diverted for urban use and irrigation along the Colorado River) were in the region of the limit-of-detection (e.g., 10 ng/L), but most were below detection limits.

Citation Information

Publication Year 2012
Title Point sources of emerging contaminants along the Colorado River Basin: Source water for the arid Southwestern United States
DOI 10.1016/j.scitotenv.2012.04.053
Authors Tammy L. Jones-Lepp, Charles Sanchez, David A. Alvarez, Doyle C. Wilson, Randi-Laurant Taniguchi-Fu
Publication Type Article
Publication Subtype Journal Article
Series Title Science of the Total Environment
Series Number
Index ID 70038711
Record Source USGS Publications Warehouse
USGS Organization Columbia Environmental Research Center